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Bench Mark Sheet for 9455866, Point Possession AK

Superseded Epoch

Large map location marker Station Location
Small red map location marker Published bench mark
Small blue map location marker Unpublished bench mark

Bench mark positions only appear on the map if their coordinates in the CO-OPS database are at the precision of degrees/minutes/seconds/and tenths of seconds. If the coordinates are less precise, the mark will not appear.

Printable version

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
Datums Page                                                        Page  1 of  7

                                                                                
Station ID: 9455866                         PUBLICATION DATE:  09/11/2014
Name:       POINT POSSESSION (T-39, OPR-469)                  
            AK
NOAA Chart: 16665                           Latitude:   61°  2.2' N (  61.03670)
USGS Quad:  POINT POSSESSION                Longitude: 150° 24.8' W (-150.41300)


To reach the bench marks from the Ted Stevens Anchorage International Airport by
helicopter, proceed SW for 26.5 km (16.5 mi) to the NW shore of Point Possession
on the Kenai Peninsula on the east shore of Cook Inlet.  The bench marks are set
in boulders along the base of the bluff.  The tide station is located at the
base of an 18 m (60 ft) high bluff and below an abandoned USCG day marker.      
 


                         T I D A L   B E N C H   M A R K S


                 PRIMARY BENCH MARK STAMPING:  5866 D 1999
                         DESIGNATION:          945 5866 D

MONUMENTATION:           Tidal Station disk                    VM#:        16049
AGENCY:                  LCMF, Inc.                            IDB PID#:        
SETTING CLASSIFICATION:  Boulder                               OPUS PID#: BBBF49
LATITUDE:   61°  2.0' N (  61.03394)          LONGITUDE: 150° 24.4' W (-150.40600)


The primary bench mark is a disk set flush atop a 2.85 m (9.4 ft) x 1.55 m (5.1
ft) x 0.30 m (1.0 ft) high boulder, 26.80 m (87.9 ft) WSW of bench mark 945 5866
C, 21.21 m (69.6 ft) SE of bench mark 945 5866 F, and 14 m (46 ft) NW of the
vegetation at the base of the bluff.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  2 of  7

                                                                                
Station ID: 9455866                         PUBLICATION DATE:  09/11/2014
Name:       POINT POSSESSION (T-39, OPR-469)                  
            AK
NOAA Chart: 16665                           Latitude:   61°  2.2' N (  61.03670)
USGS Quad:  POINT POSSESSION                Longitude: 150° 24.8' W (-150.41300)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  BM 2 1974
                         DESIGNATION:          945 5866 TIDAL 2

MONUMENTATION:           Tidal Station disk                    VM#:        14777
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Granitic boulder                      OPUS PID:        
LATITUDE:   61°  2.3' N (  61.03803)          LONGITUDE: 150° 23.7' W (-150.39533)


The bench mark is a bent disk set flush in the top of a 4 m (11 ft) x 2.2 m (7
ft) x 1.2 m (4 ft) high boulder, 66 m (217 ft) ESE of bench mark BM 1 1974,
42.10 m (138.1 ft) NW of bench mark BM  4 1974, and 22 m (72 ft) north of the
base of the bluff.    



                         BENCH MARK STAMPING:  BM 3 1974
                         DESIGNATION:          945 5866 TIDAL 3

MONUMENTATION:           Tidal Station disk                    VM#:        14778
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Granitic boulder                      OPUS PID:        
LATITUDE:   61°  2.3' N (  61.03772)          LONGITUDE: 150° 23.9' W (-150.39831)


The bench mark is a disk set in the top of a 3 m (9 ft) x 3 m (8 ft) x 1 m (4
ft) high boulder, 112 m (367 ft) SW of bench mark 945 5866 TIDAL 1, and 42 m
(138 ft) NW of the base of the bluff.

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  3 of  7

                                                                                
Station ID: 9455866                         PUBLICATION DATE:  09/11/2014
Name:       POINT POSSESSION (T-39, OPR-469)                  
            AK
NOAA Chart: 16665                           Latitude:   61°  2.2' N (  61.03670)
USGS Quad:  POINT POSSESSION                Longitude: 150° 24.8' W (-150.41300)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  BM 4 1974
                         DESIGNATION:          945 5866 TIDAL 4

MONUMENTATION:           Tidal Station disk                    VM#:        14779
AGENCY:                  National Ocean Survey (NOS)           IDB PID#:        
SETTING CLASSIFICATION:  Granitic boulder                      OPUS PID:        
LATITUDE:   61°  2.3' N (  61.03792)          LONGITUDE: 150° 23.7' W (-150.39453)


The bench mark is a disk set in the top of a 2 m (6 ft) x 1 m (3 ft) x 1 m (2
ft) high boulder, 42.10 m (138.1 ft) SE of bench mark 945 5866 TIDAL 2, and 11 m
(37 ft) north of the base of the bluff.



                         BENCH MARK STAMPING:  5866 B 1999
                         DESIGNATION:          945 5866 B

MONUMENTATION:           Tidal Station disk                    VM#:        16047
AGENCY:                  LCMF, Inc.                            IDB PID#:        
SETTING CLASSIFICATION:  Boulder                               OPUS PID:        
LATITUDE:   61°  2.2' N (  61.03589)          LONGITUDE: 150° 24.2' W (-150.40256)


The bench mark is a disk set in the top of a 2 m (8 ft) x 2 m (6 ft) x 0.7 m (2
ft) high boulder, 182 m (597 ft) NE of bench mark 945 5866 C, and 37 m (121 ft)
NW from the base of the bluff.    

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  4 of  7

                                                                                
Station ID: 9455866                         PUBLICATION DATE:  09/11/2014
Name:       POINT POSSESSION (T-39, OPR-469)                  
            AK
NOAA Chart: 16665                           Latitude:   61°  2.2' N (  61.03670)
USGS Quad:  POINT POSSESSION                Longitude: 150° 24.8' W (-150.41300)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  5866 C 1999
                         DESIGNATION:          945 5866 C

MONUMENTATION:           Aluminum marker                       VM#:        16048
AGENCY:                  LCMF, Inc.                            IDB PID#:        
SETTING CLASSIFICATION:  Aluminum alloy rod                    OPUS PID:        
LATITUDE:   61°  2.0' N (  61.03397)          LONGITUDE: 150° 24.3' W (-150.40553)


The bench mark is a disk set at the base of the bluff beneath the abandoned U.S.
Coast Guard day marker, 182 m (597 ft) SW of bench mark 945 5866 B, 27 m (88 ft)
ENE of bench mark 945 5866 D, and 3 m (10 ft) SE of the vegetation line.  The
bench mark is set 18 cm (0.6 ft) above ground, crimped to the top of an aluminum
rod driven 2.3 m (8 ft) to refusal.    



                         BENCH MARK STAMPING:  E
                         DESIGNATION:          945 5866 E

MONUMENTATION:           Bolt                                  VM#:        16050
AGENCY:                  LCMF, Inc.                            IDB PID#:        
SETTING CLASSIFICATION:  Boulder                               OPUS PID:        
LATITUDE:   61°  2.0' N (  61.03414)          LONGITUDE: 150° 24.4' W (-150.40650)


The bench mark is a 1/4 inch by 5 inch stainless steel carriage bolt set in the
top of a 2 m x 1 m (5 ft x 3 ft) boulder, 47 m (155 ft) from the base of the
bluff, 12 m (41 ft) NW of bench mark 945 5866 F, and 0.5 m (1.5 ft) above beach
level.    

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  5 of  7

                                                                                
Station ID: 9455866                         PUBLICATION DATE:  09/11/2014
Name:       POINT POSSESSION (T-39, OPR-469)                  
            AK
NOAA Chart: 16665                           Latitude:   61°  2.2' N (  61.03670)
USGS Quad:  POINT POSSESSION                Longitude: 150° 24.8' W (-150.41300)


                         T I D A L   B E N C H   M A R K S


                         BENCH MARK STAMPING:  5866 F 1999
                         DESIGNATION:          945 5866 F

MONUMENTATION:           Tidal Station disk                    VM#:        16051
AGENCY:                  LCMF, Inc.                            IDB PID#:        
SETTING CLASSIFICATION:  Boulder                               OPUS PID:        
LATITUDE:   61°  2.0' N (  61.03411)          LONGITUDE: 150° 24.4' W (-150.40628)


The bench mark is a disk set atop a 2 m (6 ft) x 1.5 m (5 ft) x 1 m (3 ft) high
boulder, 35 m (115 ft) NW of the vegetation at the base of the bluff, and 21.21
m (69.6 ft) NW of bench mark 945 5866 D.    

                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  6 of  7

                                                                                
Station ID: 9455866                         PUBLICATION DATE:  09/11/2014
Name:       POINT POSSESSION (T-39, OPR-469)                  
            AK
NOAA Chart: 16665                           Latitude:   61°  2.2' N (  61.03670)
USGS Quad:  POINT POSSESSION                Longitude: 150° 24.8' W (-150.41300)


                            T I D A L   D A T U M S 


Tidal datums at POINT POSSESSION (T-39, OPR-469) based on:

     LENGTH OF SERIES:      30 DAYS
     TIME PERIOD:           Aug 2 2008 - Aug 31 2008
     TIDAL EPOCH:           1983-2001
     CONTROL TIDE STATION:  9455920 ANCHORAGE, KNIK ARM, COOK INLET


Elevations of tidal datums referred to Mean Lower Low Water (MLLW), in METERS:

     MEAN HIGHER HIGH WATER                     MHHW   =  7.936
     MEAN HIGH WATER                            MHW    =  7.730
     MEAN SEA LEVEL                             MSL    =  4.348
     MEAN TIDE LEVEL                            MTL    =  4.202
     MEAN LOW WATER                             MLW    =  0.674
     MEAN LOWER LOW WATER                       MLLW   =  0.000

North American Vertical Datum (NAVD88)

Bench Mark Elevation Information                In METERS above:

     Stamping or Designation                    MLLW        MHW

     5866 D 1999                                 7.618   -0.112
     BM 2 1974                                   6.679   -1.051
     BM 3 1974                                   3.067   -4.663
     BM 4 1974                                   7.748    0.017
     5866 B 1999                                 4.936   -2.794
     5866 C 1999                                11.394    3.664
     E                                           3.842   -3.889
     5866 F 1999                                 5.250   -2.480


                          U.S. DEPARTMENT OF COMMERCE
                National Oceanic and Atmospheric Administration
                            National Ocean Service
                                                                   Page  7 of  7

                                                                                
Station ID: 9455866                         PUBLICATION DATE:  09/11/2014
Name:       POINT POSSESSION (T-39, OPR-469)                  
            AK
NOAA Chart: 16665                           Latitude:   61°  2.2' N (  61.03670)
USGS Quad:  POINT POSSESSION                Longitude: 150° 24.8' W (-150.41300)


                             D E F I N I T I O N S


Mean Sea Level (MSL) is a tidal datum determined over a 19-year National Tidal
Datum Epoch.  It pertains to local mean sea level and should not be confused
with the fixed datums of North American Vertical Datum of 1988 (NAVD88).

NAVD88 is a fixed datum derived from a simultaneous, least squares, minimum
constraint adjustment of Canadian/Mexican/United States leveling observations.
Local mean sea level observed at Father Point/Rimouski, Canada was held fixed as
the single initial constraint.  NAVD88 replaces NGVD29 as the national
standard geodetic reference for heights.  Bench mark elevations relative to
NAVD88 are available from NGS through the World Wide Web at 
National Geodetic Survey.

NGVD29 is a fixed datum adopted as a national standard geodetic reference for
heights but is now considered superseded.  NGVD29 is sometimes referred to as
Sea Level Datum of 1929 or as Mean Sea Level on some early issues of Geological
Survey Topographic Quads.  NGVD29 was originally derived from a general
adjustment of the first-order leveling networks of the U.S. and Canada after
holding mean sea level observed at 26 long term tide stations as fixed.
Numerous local and wide-spread adjustments have been made since establishment in
1929.  Bench mark elevations relative to NGVD29 are available from the National
Geodetic Survey (NGS) data base via the World Wide Web at 
National Geodetic Survey.

NAVD88 and NGVD29 are fixed geodetic datums whose elevation relationships to
local MSL and other tidal datums may not be consistent from one location to
another.

The Vertical Mark Number (VM#) and PID# shown on the bench mark sheet are unique
identifiers for bench marks in the tidal and geodetic databases, respectively.
Each bench mark in either database has a single, unique VM# and/or PID# assigned.
Where both VM# and PID# are indicated, both tidal and geodetic elevations are
available for the bench mark listed. The NGS's Integrated Data Base (IDB PID)
provides geodetic datum based on traditionally leveled and bluebooked ties to
the National Spatial Reference System(NSRS) https://www.ngs.noaa.gov/datasheets/.
The NGS Online Positioning User Service (OPUS PID) provides geodetic datum based
on GPS position & tie it to the NSRS https://www.ngs.noaa.gov/OPUS/.

The NAVD88 elevation is shown on the Elevations of Tidal Datums Table Referred
to MLLW only when two or more of the bench marks listed have NAVD88 elevations.
The NAVD88 elevation relationship shown in the table is derived from an average
of several bench mark elevations relative to tide station datum.  As a result of
this averaging, NAVD88 bench mark elevations computed indirectly from the tidal
datums elevation table may differ slightly from NAVD88 elevations listed for
each bench mark in the NGS database.

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Products available at 9455866 Point Possession, AK

Revised: 08/08/2018
NOAA / National Ocean Service
Web site owner: Center for Operational Oceanographic Products and Services